Liver transplantation is the sole life-saving treatment for patients with end stage liver disease (ESLD). Unfortunately many patients listed for transplant will become too sick for transplant or die while awaiting an organ. Given the gravity of the consequences of failing to receive a liver transplant efforts have been made to establish an allocation system that is equitable and fare. In 2002, the Model for End Stage Liver Disease (MELD) score, which is derived from a patient's INR, creatinine, and bilirubin was implemented, with these goals in mind. The MELD score has decreased wait time and overall waitlist mortality. However in 2008 a disturbing gender disparity in liver transplantation was identified. I the MELD era women are more likely than men to become too sick or die on the transplant list and less likely than men to receive liver transplantation. Research in this area has identified gender differences in creatinine and size as important contributing factors. However neither of these hypotheses has fully explained the disparity in rates of receiving a transplant. The gender disparity in transplantation is complex and multifactorial; it involves donor, recipient, and cente factors. To further understand these factors gender differences in organ offer and acceptance patterns should be explored. Aim 1 of our study will seek to determine if there are gender differences in organ offers. Receiving an organ offer is based solely on ones MELD score and blood type. We hypothesize that women will have lower creatinine and therefor lower MELD scores. This will translate into women receiving fewer organ offers than men. In aim 2 we will explore gender difference in organ acceptance patterns. In order for a patient to receive a transplant, an organ must be offered and then accepted by the transplant team. A transplant team's decision to accept or decline an organ is a complex one. Getting at the crux of gender disparities in transplantation will require us to explore these complexities. Finally we believe tht donor- recipient size matching is an important factor when a transplant team decides to accept or decline an organ. In aim 3, we will explore if size matching disproportionately disadvantages women by exploring differences in rates of organs being declined because of size. The proposed research project will be in the context of the applicant working towards a Masters of Science in Clinical Epidemiology, whereby didactic learning in the classroom, focusing on fundamentals of epidemiology, study design, and statistical and analytic methods of research will enhance and guide the research process of the applicant. The long-term objectives of the applicant for this project are to collect and analyze the data, prepare manuscripts for publication and build upon the data as part of a future application for a K award.